Presently available automatic tool changers typically utilize an internal air cylinder to actuate a gripping mechanism for locking two mating flanges together. In another present day technique, an internal actuator is utilized to push a tapered cup over steel balls forcing them into a groove to obtain a locking action. In still another present day technique, tapered elements are rotated relative to one another to produce a locking effect through the employment of a eccentric collar. The major problem with present day tool changing devices is that they are typically large and heavy and the smaller units available on the market are incapable of providing an adequate number of electrical lines and pneumatic ports which is important in order to provide the capability of use with a variety of different end effectors.